<template>
  <view>
    <!-- 使用自定义的搜索组件 -->
    <!-- <my-search :bgcolor="'pink'" :radius="3"></my-search> -->
    <my-search @click="gotoSearch"></my-search>
    <view class="scoll-view-container">
      <!-- 左侧的滚动视图区域 -->
      <scroll-view class="left-scroll-view" scroll-y :style="{height:wh+'px'}">
        <block v-for="(item,i) in cateList" :key="i">
          <view :class="['left-scroll-view-item',i===active?'active':'']" @click="activeChanged(i)">{{item.cat_name}}
          </view>
        </block>
      </scroll-view>

      <!-- 右侧的滚动视图区域 重置滚动条-->
      <scroll-view class="right-scroll-view" scroll-y :style="{height: wh +'px'}" :scroll-top="scrollTop">
        <view class="cate-lv2" v-for="(item2, i2) in cateListL2" :key="i2">
          <view class="cate-lv2-title">/ {{item2.cat_name}} /</view>
          <!-- 动态渲染三级分类的列表数据 -->
          <view class="cate-lv3-list">
            <!-- 三级分类 Item 项 -->
            <view class="cate-lv3-item" v-for="(item3, i3) in item2.children" :key="i3" @click="gotoGoodsList(item3)">
              <!-- 图片 -->
              <image :src="item3.cat_icon"></image>
              <!-- 文本 -->
              <text>{{item3.cat_name}}</text>
            </view>
          </view>
        </view>
      </scroll-view>

    </view>
  </view>
</template>

<script>
  import badgeMix from '@/mixins/tabbar-badge.js'
  export default {
    mixins: [badgeMix],
    data() {
      return {
        //当前设备可用高度
        wh: 0,
        //分类列表数据
        cateList: [],
        //二级分类列表数据
        cateListL2: [],
        //当前选中项的索引，默认让第一项被选中
        active: 0,
        // 滚动条距离顶部的距离
        scrollTop: 5000
      };
    },
    onLoad() {
      const sysInfo = uni.getSystemInfoAsync()
      this.wh = sysInfo.windowHeight
      this.getCateList()
    },
    methods: {
      async getCateList() {
        //发起请求
        const {
          data: res
        } = await uni.$http.get('/api/public/v1/categories')
        //判断是否获取失败
        if (res.meta.status !== 200) return uni.$showMsg()
        //转存数据
        this.cateList = res.message
        console.log("分类", res)
        //为二级分类赋值
        this.cateListL2 = res.message[0].children
      },
      activeChanged(i) {
        this.active = i
        this.cateListL2 = this.cateList[i].children
        // 让 scrollTop 的值在 0 与 1 之间切换
        this.scrollTop = Math.random()
        // this.scrollTop = this.scrollTop === 0 ? 1 : 0
        console.log("this.scrollTop", this.scrollTop)
        // 可以简化为如下的代码：
        // this.scrollTop = this.scrollTop ? 0 : 1
      },
      // 点击三级分类项跳转到商品列表页面
      gotoGoodsList(item3) {
        uni.navigateTo({
          url: '/subpkg/goods_list/goods_list?cid=' + item3.cat_id
        })
      },
      //跳转到分包中的搜索页面
      gotoSearch(){
        uni.navigateTo({
          url:'/subpkg/search/search'
        })
      }
    }
  }
</script>

<style lang="scss">
  .scoll-view-container {
    display: flex;

    .left-scroll-view {
      width: 120px;

      .left-scroll-view-item {
        background-color: #f7f7f7;
        line-height: 60px;
        text-align: center;
        font-size: 12px;

        &.active {
          background-color: #ffffff;
          position: relative;

          //渲染激活想左侧的红色指示边线
          &::before {
            content: '';
            display: block;
            width: 3px;
            height: 30px;
            background-color: #C00000;
            position: absolute;
            left: 0;
            top: 50%;
            transform: translateY(-50%);
          }
        }
      }
    }

    .cate-lv2-title {
      font-size: 12px;
      font-weight: bold;
      text-align: center;
      padding: 15px 0;
    }

    .cate-lv3-list {
      display: flex;
      flex-wrap: wrap; //自动换行

      .cate-lv3-item {
        width: 33.33%;
        display: flex;
        flex-direction: column;
        justify-content: center;
        align-items: center;
        margin-bottom: 10px;

        image {
          width: 60px;
          height: 60px;
        }

        text {
          font-size: 12px;
        }
      }
    }
  }
</style>